Magnetic resonance and microwave resistance modulation in the van der Waals ferrimagnet Mn 3 Si 2 Te 6

This is the authors' abstract. We don't add key points for this paper.

Unconventional magnetoresistance is a fascinating quantum phenomenon that continues to draw significant interest in condensed-matter physics. Mn₃Si₂Te₆ has emerged as such a novel magnetoresistance (MR) material, notable for its largest MR exceeding conventional colossal magnetoresistance materials and pronounced directional anisotropy. Despite extensive research, the mechanisms driving MR in Mn₃Si₂Te₆ remain elusive [Ni et al. Phys. Rev. B 103, L161105 (2021); Ye et al. Phys. Rev. B 106, L180402 (2022); Zhang et al., Nature 611, 467 (2022); Gu et al., Nat. Comm. 15, 8104 (2024)]. In this work, we explore the magnetic resonance of Mn₃Si₂Te₆ and observe a reduced g factor for magnetic fields applied along the crystalline c axis compared to the ab plane, indicating a substantial orbital magnetization contribution along the c axis. Furthermore, we detect resistance modulation under resonance conditions, suggesting that MR in Mn₃Si₂Te₆ is sensitive to the out-of-plane spin polarization. These findings shed new light on the role of orbital magnetic moment in Mn₃Si₂Te₆, offering a deeper understanding of the interplay between spin, orbital, and lattice degrees of freedom of electrons.